CH340G SMD IC USB to TTL converter UART SOP16 WCH CH340G

Product Overview:

A high-performance USB bus adapter chip engineered to implement USB-to-serial port (UART) or USB-to-print port conversions. Operating as a full-speed USB device, it emulates a standard asynchronous serial interface, providing full duplex UART communications with independent internal transmit and receive buffers. It natively supports common MODEM contact signals and hardware handshaking, enabling old serial peripherals to upgrade directly to the USB bus or allowing computers to seamlessly expand additional COM ports without software modifications.

Core Specifications:

Manufacturer: WCH (Jiangsu Qinheng Co-share Electronics Co., Ltd. / 南京沁恒微电子)

Package Type: SOP-16, SSOP-20, SOP-8, ESSOP-10, and MSOP-10 (Variant dependent, e.g., CH340G, CH340C, CH340X, CH340E)

Function: USB to Serial / UART Adapter Chip

Input Channels: Full-Speed USB Device Interface (UD+ and UD- data lines)

Control Interface: Hardware Asynchronous Serial UART Interface (TXD, RXD) with auxiliary MODEM signals (RTS, DTR, DCD, RI, DSR, CTS)

Features

• Full-Speed USB Compliance: Fully compatible with the USB V2.0 specification, utilizing a hardware full-speed interface requiring standard driver mapping.

• Flexible Baud Rate Support: Built-in communication engine supports a broad spectrum of hardware baud rates ranging from 50 bps up to 2 Mbps.

• Extensive MODEM Signaling: Hardware controls manage multiple handshaking and state tracking signals including RTS, DTR, DCD, RI, DSR, and CTS.

• Multi-Standard Level Translation: Easily pairs with external level-shifting components to emulate rugged RS232, RS485, and RS422 communication links.

• Dual-Voltage Operation: Operates reliably across both 5V and 3.3V power structures, with a dedicated internal low-dropout regulator for 3.3V power rails.

• Minimal External Component Needs: Modern variants feature integrated clock oscillators, integrated power-on-reset blocks, and internal EEPROMs to minimize board-space overhead.

• Microcontroller Micro-Download Support: Includes specialized hardware functionality (such as on select variants like CH340X) that aids in executing one-key bootloader downloads to host microcontrollers.

Applications

• USB to RS232/RS485 Serial Cables: Acts as the main translation bridge inside communication dongles used to talk with industrial devices.

• Microcontroller Development Boards: Employs localized USB-to-UART routing for programming and debugging host microcontrollers (such as Arduino or STC modules).

• Legacy Hardware Modernization: Embedded within older POS printers, industrial equipment consoles, and modems to adapt them to modern USB interfaces.

• Automated Test and Measurement: Connects lab monitoring instruments and data collection hardware straight to computer diagnostic programs.